Project Summary/Abstract: Transgenic & Genetic Constructs (TGC) The Transgenic & Genetic Constructs (TGC) Shared Resource, directed by Dr. Steven Fiering, provides services for generating, maintaining, and genetically and experimentally manipulating genetically modified mice (GMM). TGC provides mouse, cell, and genetic construct manipulation and speed congenics to NCCC researchers. These technical services are provided by 3 technical specialists, one for the mouse work, one in Embryonic Stem cell culture and general molecular biology research, and the third performing automated SNP genotyping assays using Illumina(R) technology. Newer services of TGC involve using techniques to generate mice with either humanized immune systems or humanized livers. A colony of immunodeficient Nod/SCID/IL2gamma receptor knockout mice (NSG) is in high demand by NCCC researchers, because they are the optimal strain for establishing xenografts of human tumor cell lines. For many GMM-based experiments, knowing the genetic background carrying the genetic modifications is crucial. Traditionally, a 3-year process of random backcrossing has been required to change the genetic background of a GMM. Dr. James Gorham, with assistance from Fiering, established a speed congenic facility that uses automated SNP genotyping to perform speed congenic and related services on GMM. Merging TGC with the Speed Congenics Resource expanded TGC services to provide rapid identification of male breeders with the highest proportion of the desired background; this has cut the required number of backcross generations from 10 to 5. On a daily basis, Fiering focuses primarily on the transgenic mouse generation and utilization services, and Gorham focuses on the speed congenics, but they work together to direct TGC as one unit. Combining these services into TGC has enabled us to expand and improve services and efficiency to better serve our clients. The generation and utilization of GMM is a technically complex field, with new techniques rapidly evolving. TGC constantly is developing new technical capabilities and new services to broaden our ability to support GMM usage in cancer research. The vast majority of services provided by TGC utilize equipment (e.g., tissue culture hoods, molecular biology equipment, microscopes, and injection devices and surgical tools) that have been in the lab for most of the 16 years of its existence. Biological systems in use at a given time, technological approaches and the faculty and their interests constantly evolve. Our ability to provide the broad range of services is dependent primarily on the accumulated skill of the personnel performing the service tasks, such as culturing ES cells, manipulating embryos, using recombineering to generate constructs, and speed congenic analysis. TGC services are an important component of the research conducted by 4 of 6 NCCC Research Programs (Cancer Mechanisms, Molecular Therapeutics, Cancer Imaging & Radiobiology, and Immunology & Cancer Immunotherapy). TGC also has entered into shared service agreements with the University of Vermont Transgenic Shared Resource and Jackson Labs to avoid overlapping services and to refer clients for services not available at their institution.